Grate-bar.



No.741,546. PATENTED'OCTVIB',1903; T. J. PRITCHARD. S

GRATE BAR.

APPLIOATION FILED APR. 23, 1903.

N0 MODEL.

all

1m: norms PETERS co. Pnoro-uma, WASHINGTON n. c.

' one example of my invention, while the claims UNITED STATES- Patented October 13, 1909;.

PATENT OFFICE.

G RATE- B AR.

SPECIFICATION forming part of Letters? Patent No. 741,546, dated October 13, 1903.

Application filed Ap'ril2S-,1903. ammo. 153.991. woman.)

the followingis a full, clear, and exact description.

This invention relates to a hollow gratebar through whicha current of air is passed to accelerate combustion of the fuel. The grate-bar is adapted especially to be used in connection with a bridge-wall and according to the construction here shown is formed of a lower or body section and a mating top section, which latter is raised above the ordinary level of the grate, the top section hav ing shielded orifices therein, through'which the draft is passed into the fuel. The bridgewall is formed with a draft-tunnel, and airpipes pass from this tunnel into the hollow grate-bars, said bars having adjacent to the bridge-wall two or more openings discharging the air-current directly upon the wall,

and thereby acting as twyers to permit sup-.

plying oxygen to the gases passing over the bridge-wall.

This specification is an exact description of define the actual scope thereof.

Reference is to be had to the accompanying drawings, forminga part of this specification, in which similar characters of reference indicate corresponding parts in all the views.

Figure l is a perspective view of the invention. Fig. 2 is a longitudinal section of the grate-bar, and Fig. 3 is a cross-section on the line 3 3 of Fig. 2.

As shown best in Figs. 2 or body member a is formed in the shape of a trough and has extensions a at its ends,

. which rest on the bridge-wall andfurnacesetting, as shown in Fig. 1. The body member is also formed with transversely-extending bracing-ribs (1 having openings at their lower sides to permit the ashes to pass downand 3, the bottom 22 which prevent the entry .of ashes into the grate-bar. 'The said sections Cb and b of the bar are held together by tie-bolts c and d, the tie-bolt 0 being located at the end portions of the grate-bar and the tie-bolt (1 being located atthe middle, all of said bolts extending vertically and the bolt d serving also to hold in place a closure 6, which covers the opening a. d indicates a key by which the parts (I and e are removably connected.

As shown in Fig. 1, the grate-bar is preferably arranged with one end on the furnacesetting and the other end on the bridge-wall, although .I prefer to arrange between each of my improved grate-bars, a number of the ordinary gratabars-f, which lie in a plane belowthe top b,so. thatv the fuel spread over this composite grate will bebest subjected to and mingle with the gases of combustion at this point, so as to'bring about efiective combustion of the fuel.

Air is supplied to the interiors of the gratebars by means of air-pipes g, which are engaged with nipples a on the lower or body sections a and which pass from said nipples front of the bridge-wall into the draft-tunnel formed therein, the receiving ends of the airpipes being flared or funnel-shaped, as indicated atg in Fig. 1.

. With the parts assembled as in Fig. 1 it is my purpose to supply air to the fire -box through the ash-pit, as usual, and also to per- .mit an additional supply to pass through the pipes g into my improved hollow grate-bars. This provides for the best possible supply of oxygen, and consequently for a thorough and economic utilization of the fuel employed. The grate-bar being sectional, as showrnmay be readily repaired, since the greatest heat will be on the top section b, and if this should become injured it may be removed and a new section applied to the old body, thus bringings to extend over the top of the bridge-wall ing about a great saving, as will be apparent.

the action of. the airsupplied to the furnace.

downward and thence rearward through the.

Various changes in the form, proportions, and minor details of my invention may be resorted to at will without departing from the spirit and scope thereof. Hence I consider myself entitled to all such variations as may lie within the intent of my claims.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. A hollow grate-bar, comprising upper and lower longitudinal sections, each of approximately the length of the bar, the edges of which sections are engaged together to form the grate-bar and the upper section having an air-discharge orifice therein, means for fastening said sections in place, the bottom section having an orifice for the introduction of a current of air into the grate-bar, and a bracing rib located in the bottom section and extending from side to side thereof.

2. A hollow grate-bar, comprising upper and lower longitudinal sections, each of approximately the length of the bar, the edges of which sections are engaged together to form the grate-bar and the upper section having an air-discharge orifice therein, and means for fastening said sections in place, the bottom section having an orifice for the introduction of a current of airinto the grate-bar, the bottom section being formed with an ashoutlet opening and a closure for said open ing, the means for holding the sections engaged comprising a tie-bolt engaged with said closure and extending upward into engagement with the upper section of the grate-bar.

3. A hollow grate-bar, comprising upper and lower sections each of approximately the length of the grate-bar, said sections, having their edges engaged together, and the upper section having an air-discharge opening and the lower section having an air-inlet opening and an ash-outlet opening, a closure for the ash-outlet opening, a tie-rod engaged with the closure and extending upward to the upper section of the grate-bar, whereby to hold the grate-bar sections engaged and to keep the closure in position, and a strengthening-rib located in the lower section and extending transversely from side to side thereof.

4. The combination with a bridge-wall, of a hollow grate-bar, and means for supplying a current of air thereto, said grate-bar having an air-discharge opening in the end adjacent to the bridge-wall and also having a horizontally-disposed shield juxtaposed to said opening directing the air-current horizontally toward and over the bridge-wall.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

'lIlllODOll-Il JOSEPH lIRl'l'CllAltl).

Vituesscs:

A. A. BROWNE, A. J OLY. 

